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51.
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Exercise is the strongest stress to which the body is ever exposed. The body responds to this stress through a set of physiological changes in its metabolic, hormonal and immunological systems. In this study, responses of the immune system to the long-term aerobic and anaerobic exercises have been investigated. Twenty-four sedentary male university students and officers participated in this study. Subjects were divided into two groups, each consisting of twelve people. Group-1 (age: 25.67 +/- 3.79 years, height: 174.83 +/- 5.15 cm, body mass: 72.17 +/- 8.05 kg) and Group-2 (age: 24.83 +/- 2.89 years, height: 175.3 +/- 6.68 cm, body mass: 70.67 +/- 6.15 kg). After physical examinations of the two groups, resting ECG, respiratory function tests and metabolic tests with the use of the breath by breath method were completed, and anerobic heart rates at the threshold level were determined. The first group was subjected to exercise using Monark ergometry cycles at a heart rate 10% below the threshold level for 8 weeks, 3 days a week, 30 min a day. The second group exercised at a heart rate 10% above the threshold level for 8 weeks, 3 days a week, 20 min a day. Heart rates were checked with the Polar Test during exercises. Pre-exercise (Ep) venous blood samples were taken from each group before their 1st and 24th exercises. Hb (gr), Hct (%), erythrocyte (x10(6)/microl), leukocyte (x10(6)/microl), leukocyte subpopulations (neutrophil, lymphocyte, monocyte, eosinophil, basophil %) and thrombocyte (x10(6)/microl) values were determined. CD3, CD4, CD8, CD19 and CD56 values were determined by Flow Cytometry method using monoclonal antibodies. The chronic effects of exercise were examined through a comparison of Ep blood samples at the 1st exercise with Ep blood samples at the 24th exercise. While the increase in the total leukocyte number was significant (p<0.05) in the first group, increase in the second group was found to be non-significant. When percentiles of leukocyte subpopulations were taken into consideration, changes in the first and second group were found to be non-significant. When lymphocyte subgroups were examined; in the first group a decrease in CD3 and CD4 percentiles to 7% and 12%, respectively (p<0.05) and a 65% increase (p<0.01) in the CD56 value were observed. In the second group a decrease in CD3 and CD4 percentiles to 13% and 17%, respectively (p<0.05) and a 73% increase (p<0.01) in the CD56 value were observed. The Sample-t Test and The Wilcoxon Test were used for statistical analysis.  相似文献   
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Antitumor agents are used in therapy against many forms of human cancer. One of these is mitomycin-C (MMC). As with many agents, it can interact with biological molecules and can induce genetic hazards in non-tumor cells. One of the possible approaches to protect DNA from this damage is to supply antioxidants that can remove free radicals produced by antitumor agents. Lipoic acid (LA) is known as one of the most powerful antioxidants. The aim of this study was to investigate antigenotoxic effects of LA against MMC induced chromosomal aberrations (CA), sister chromatid exchanges (SCE) and micronucleus (MN) formation in human lymphocytes. Lymphocytes were treated with 0.2 μg MMC/heparinized mL for 48 h. Three different concentrations (0.5, 1, 2 μg/mL) of LA were used together with MMC in three different applications; 1 h pre-treatment, simultaneous treatment and 1 h post-treatment. A negative, a positive and a solvent control were also included. In all the cultures treated with MMC + LA, the frequency of abnormal cells and CA/cell significantly decreased compared to MMC. Statistically significant reduction was also observed in SCE/cell and MN frequencies in all treatments. These results demonstrated anticlastogenic and antimutagenic effects of LA against MMC induced genotoxicity. LA showed the most efficient effect during 1 h pretreatment. On the other hand, MMC + LA treatments induced significant reduction in mitotic index than that of MMC treatment alone. These results are encouraging that LA can be a possible chemopreventive agent in tumorigenesis in both cancer patients and in health care persons handling anti-cancer drugs.  相似文献   
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OBJECTIVES:

Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS) is a newly defined disease in neuropsychiatry and occurs with an autoimmune mechanism after Group A Beta Hemolytic Streptococcus (GABHS) infection. Tumor necrosis factor (TNF), encoded by TNF-α gene has an important role in the apoptotic mechanisms of autoimmune diseases. Recently, TNF-α polymorphisms and autoimmune/psychiatric disorders have been reported to be related. In this regard, we focused on to investigate a possible relation between the TNF-α gene promoter region−308 G/A and − 850 C/T polymorphisms and PANDAS.

MATERIALS AND METHODS:

In this study, ages of PANDAS patient and control groups were ranging from 4 years to 12-year-old. Patient group includes childhood onset PANDAS patients (n = 42) and control group includes healthy children (n = 58). Diagnoses have been carried out according to Diagnostic and Statistical Manual of Mental Disorder (DSM-IV) criteria with Affective Disorders and Schizophrenia-Present and Lifetime (KSAD-S-PL) and Children Yale-Brown Obsessive Compulsive Scale Moreover, PANDAS criteria established by the American National Psychiatry Institute have been employed for diagnoses. For identifying polymorphisms; Polymerase Chain Reaction, Restriction Fragment Length Polymorphism and Polyacrylamid Gel Electrophoresis were used.

RESULTS AND DISCUSSION:

For −308 polymorphism, 37 of 42 PANDAS patients’ results and for −850 C/T polymorphism, 38 of 42 PANDAS patients’ results were obtained. According to our statistical analysis there is a positive relationship between PANDAS patients for −308 G/A polymorphism but not for −850 C/T polymorphism. There is no positive relationship between −308 G/A polymorphism and antistrep-tolysin O (ASO) titers and no relationship between −850 C/T polymorphism and ASO titers. We found, however, positive relationship between genders of patients (boys) and the disease. According to our results, we propose that the AA polymorphism of −308 G/A polymorphism can be used as a molecular indicator for PANDAS.  相似文献   
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Serotonin [5-hydroxytryptamine (5HT)] is a vasoconstrictor that also acts as a developmental signal early in embryogenesis. The 5HT transporter (SERT) on the membranes of the placental trophoblast cells controls 5HT levels in the maternal bloodstream to maintain stable transplacental blood flow and simultaneously provide 5HT to the embryo. The 5HT uptake rate of placental SERT is important for both the mother and the developing embryo. The impact of glucose on the placental SERT system during diabetic pregnancy is not known. The present in vitro study investigated this important issue in human placental choriocarcinoma (JAR) cells that were cultured for 24-96 h in a medium containing either 5.5 (physiologic concentration) or 25 mmol/L D-glucose (diabetic-like concentration). The 5HT uptake rates of the cultured cells were not altered at exogenous D-glucose concentrations in the range of 5.5-15 mmol/L, but were decreased significantly at a diabetic-like concentration (>or=25 mmol/L). To understand better the role of glucose on the placental 5HT system, we first characterized SERT in JAR cells at different cell-cycle phases and then determined the expression levels of SERT on the plasma membrane and in the intracellular pools of JAR cells at the late-S and G2 phases, where the uptake rates were decreased 73% under diabetic-like glucose concentrations. Finally, the importance of self-association of SERT molecules was examined. In JAR cells co-expressing Flag- and myc-tagged SERT, myc-antibody precipitated 70% of Flag-SERT, indicating that a large percentage of SERT proteins exist as oligomers in situ. Under diabetic conditions, myc-antibody no longer precipitated Flag-SERT, suggesting a disruption in the aggregation of SERT molecules. Therefore, we propose that under uncontrolled diabetic conditions, glucose down-regulates 5HT uptake rates of placental SERT by interfering with its functional expression in a cell-cycle-dependent manner.  相似文献   
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One-third of all individuals with epilepsy are resistant to antiepileptic drug (AED) treatment. Antiepileptic treatment response has been suggested to be modulated by genetic polymorphisms of drug efflux transporters. Several polymorphic variants within the multidrug resistance 1 (MDR1) gene, which encodes the major transmembrane efflux transporter P-glycoprotein, have been proposed to be associated with AED resistance in epilepsy patients. The aim of this study was to evaluate the effect of C3435T and G2677T/A polymorphisms of MDR1 on AED resistance in Turkish children with epilepsy. MDR1 C3435T and G2677T/A were genotyped in 152 patients with epilepsy, classified as drug-resistant in 69 and drug-responsive in 83. Genotypes of the C3435T and G2677T/A polymorphisms were determined by polymerase chain reaction followed by restriction fragment length polymorphism. Genotype and allele frequencies of C3435T and G2677T/A polymorphisms of the MDR1 gene did not differ between drug-resistant and drug-responsive epilepsy patients. Our results suggest that MDR1 C3435T and G2677T/A polymorphisms are not associated with AED resistance in Turkish epileptic patients. To clarify the exact clinical implication of the MDR1 polymorphisms on the multidrug resistance in epilepsy, further investigations in various ethnic populations would be necessary.  相似文献   
60.
The genotoxic and cytotoxic effects of exogenous polyamines (PAs), putrescine (Put), spermidine (Spd), spermine (Spm) and PA biosynthetic inhibitors, alpha-difluoromethylornithine (DFMO), cyclohexilamine (CHA), methylglioxal bis-(guanylhydrazone) (MGBG) were investigated in the root meristems of Allium cepa L. The reduction of mitotic index and the induction of chromosomal aberrations such as bridges, stickiness, c-mitotic anaphases, micronuclei, endoredupliction by PAs and PA biosynthetic inhibitors were observed and these were used as evidence of genotoxicity and cytotoxicity.  相似文献   
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